What is the percent of the fern spore 2 in the sediment of the Early Tertiary? You may Write a range.

the truman doctrine was an american foreign policy whose stated purpose was to counter soviet geopolitical expansion during the cold war. it was announced to congress by president harry s. truman on march 12, 1947, and further developed on july 12, 1948, when he pledged to contain threats to greece and turkey.

a

explanation:

many plants naturally reproduce this way, but it can also be induced artificially. horticulturalists have developed asexual propagation techniques that use vegetative plant parts to replicate plants. success rates and difficulty of propagation vary greatly. monocotyledons typically lack a vascular cambium and therefore are harder to propagate.

straight or amphibians are homeothermic to thermal

desert perennials often survive by remaining dormant during dry periods of the year, then springing to life when water becomes available. most annual desert plants germinate only after heavy seasonal rain, then complete their reproductive cycle very quickly.